San Francisco Giants starting pitcher Jeff Samardzija (29) walks off the mound after pitching against the Arizona Diamondbacks at AT&T Park in San Francisco, California, on August 6, 2017. (Stan Olszewski/Special to S.F. Examiner)

The San Francisco Giants’ focus this offseason centered around revamping their offense, which was — to put it kindly — weak in 2017.

Manager Bruce Bochy has to be pleased with what he’s seen from his regulars in Spring Training. Joe Panik and Brandon Belt — who project to hitting 1-2 against right-handed pitching this season — have shown out, and although they’ve been in-and-out of the preseason lineup, the trio of Andrew McCutchen, Buster Posey, and Evan Longoria have looked like their usual selves.

Coming off of a 98-loss season, it’s imperative the Giants get off to a hot start, which won’t be easy considering 19 of their first 26 games are against teams who made the postseason in 2017, including 10 against the Dodgers.

While the offense appears to be vastly improved, the starting rotation has disappointed — and it’s something that could hamper the Giants all season.

Madison Bumgarner seems primed to have a monster season as opponents have batted a measly .217 against the ace who’s struck out 27 batters in 19 innings.

As long as he stays off of dirt bikes, he’s going to be fine.

But, that’s where the good news ends. Before breaking Spring Training to head back to the Bay Area, Bumgarner looks like the only sure thing in the starting rotation.

Jeff Samardzija could be a facing a devastating shoulder injury. After getting rocked in a minor-league game Wednesday, the right-hander underwent an MRI on his throwing shoulder. Results of the MRI have yet to be released, but a disabled list stint is highly likely for the 33-year old.

Obviously, this is an unfortunate development for a club desperately trying to prove that 2017 was a fluke, but something had to be up with Samardzija, who had 10.64 ERA in four Cactus League starts while seeing a dip in velocity with his fastball, down to 89-90 as opposed to his normal 93-94 heater.

Who knows how long the Shark will be out. He ate up 207.2 innings with 205 Ks last season, and although his ERA hovered at 4.42, he recorded a career-best 6.41 strikeouts per walk and posted the majors’ best walk rate among qualifying pitchers.

So now the onus is on Johnny Cueto to pitch like it was 2016. It will ease the load of a bullpen that will more than likely be asked to be on alert with Chris Stratton and Ty Blach manning the back end of the rotation.

He’s had a rough Spring Training, with a 5.79 ERA and opponents hitting .308 against him. Nobody will panic. Pitchers usually ease into the season, using the Cactus League to work on pitches and build their arm strength.

Yet Samardzija’s status will undoubtedly hurt the Giants. How bad? Bochy and longtime Oakland Athletics pitching coach Curt Young might be forced to rely on lefty Derek Holland to revive his career.

In the meantime, the Giants will break camp with a sour taste in their mouth due to Samardzija’s shoulder issue, but they have the players to not let it wreck their season.

But if Cueto struggles, things can go haywire in a hurry for the Giants.

Bonta Hill of 95.7 The Game can be heard from 12-3 on the Greg Papa Show. Born and bred in San Francisco, he is a sports junkie who loves to sit in the lab (home), eats breakfast food for dinner, and has a newfound love for tequila. Follow at your own risk on Twitter @BontaHill.